Magnetic resistance device for upright bikes

ABSTRACT

A magnetic resistance upright bike includes a frame and a driving wheel and a fly wheel are connected to the frame wherein the fly wheel is driven by the driving wheel. A magnetic resistance device includes a support member fixed on the frame and a magnet assembly is connected on the support member. The magnet assembly includes two magnets supported on the support member and the fly wheel is rotatably located between the two magnets. A circuit board is electrically connected to the two magnets and a control device is connected to the circuit board. The gap between the fly wheel and the magnets are fixed and the magnetic force can be controlled by adjusting the current powering the magnets.

FIELD OF THE INVENTION

The present invention relates to a magnetic resistance device forupright bikes and the device is easily assembled and manufactured andsuitable for different types of upright bikes.

BACKGROUND OF THE INVENTION

A conventional upright bike 70 with a magnetic resistance device 76 isdisclosed in FIG. 9, and generally includes a bike frame 72 and atransmission device 74 which is connected to the frame 71 and iscomposed of a drive wheel 742 with a crank connected thereto, and a flywheel 741 which is rotated by rotation of the crank by the users. Themagnetic resistance device 76 includes an electric magnet 761 which iscomposed of silicon steel strips and coils. A control device 762 isconnected to the magnet 761 so that the user can operate the controldevice 762 to control the current passing through the magnet 761 tocontrol the magnetic resistance between the magnet 761 and the fly wheel741. The silicon steel strips have to be made according to the curvatureof the fly wheel 741 so as to keep an even gap between the fly wheel 741and the silicone steel strips. However, the sizes of the fly wheels 741may vary for different types of upright bikes so that the manufacturershave to prepare different molds for the manufacture. This increases themanufacturing cost.

Another conventional magnetic resistance upright bike 80 is disclosed inFIGS. 10 and 11, and includes a frame 82 with a transmission device 84which includes a drive wheel 841 and a fly wheel 842 which is rotated bythe rotation of the crank on the drive wheel 841 by the users. Amagnetic resistance device 86 is located at a distance from an outerperiphery of the fly wheel 842 so as to provide a magnetic resistance tothe fly wheel 842. The magnetic resistance device 86 includes a supportmember 861 on which a plurality of permanent magnets 862 are connected,a spring 863, a cable 864, a threaded rod 865 and a nut 866. The spring863 has one end fixed to the support frame 861 and the other end of thespring 863 is connected to the frame 82. The spring force of the spring863 can be adjusted by movement of the threaded rod 865 and the cable864 and in turn to adjust the angle of the support member 861. Thespring 863 keeps the support member 861 to have a tendency to maintain at the position where a certain gap is defined between the periphery ofthe fly wheel 842 and the magnets 862 connected on the support member861. A link 865 has one end pivotably connected to a base by a rivet 866and the other end of the link 865 is connected to the other end of thecable 864. The user may operate the link 865 to adjust the width of thegap between the support member 861 and the periphery of the fly wheel842. However, the pivotable support member 861 cannot keep the gapprecisely as desired and the spring 863 has an inherent fatigue problem.

The present invention intends to provide a magnetic resistance devicefor an upright bike wherein the magnets are located on two sides of thefly wheel and are manufactured modularized so as to obtain an economicaland compact magnetic resistance device.

SUMMARY OF THE INVENTION

The present invention relates to a magnetic resistance upright bikewhich comprises a frame and a transmission device is connected to theframe. The transmission device includes a driving wheel and a fly wheelwhich is driven by the driving wheel. A magnetic resistance deviceincludes a support member fixed on the frame and a magnet assemblyconnected on the support member. Two magnets are supported on thesupport member and the fly wheel is rotatably located between the twomagnets. A circuit board is electrically connected to the two magnetsand a control device connected to the circuit board.

The fly wheel is located between the two magnets so that the magnets arenot necessary made in different shapes according to the sizes of the flywheel, so that the magnet assembly can be made modularized which is lessexpensive when compared with the conventional magnetic resistancedevices.

The present invention will become more obvious from the followingdescription when taken in connection with the accompanying drawingswhich show, for purposes of illustration only, a preferred embodiment inaccordance with the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded view to show the magnetic resistance device andthe upright bike of the present invention;

FIG. 2 is a perspective view to show that the magnetic resistance deviceis connected to the upright bike of the present invention;

FIG. 3 is a side view of perspective view to show the upright bike withthe magnetic resistance device of the present invention;

FIG. 4 is an end view to show that the fly wheel is rotatably locatedbetween the two magnets of the magnetic resistance device of the presentinvention;

FIG. 5 shows that the magnetic resistance device is connected to anotherposition relative to the fly wheel;

FIG. 6 shows another embodiment of the support member of the magneticresistance device of the present invention;

FIG. 7 shows two sets of the magnetic resistance device of the presentinvention are used on one upright bike;

FIG. 8 shows another embodiment of the upright bike of the presentinvention;

FIG. 9 shows a conventional magnetic resistance device on an uprightbike;

FIG. 10 shows another conventional magnetic resistance device on anupright bike, and

FIG. 11 shows that the support member of the magnetic resistance devicein FIG. 10 is pivoted away from the fly wheel.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIGS. 1 to 4, the upright bike of the present inventioncomprises a frame 10 including two posts and a transmission device 20 isconnected to the frame 10. The transmission device 20 includes a drivingwheel 21 and a fly wheel 23 which is driven by the driving wheel 21 by abelt or a chain. The fly wheel 23 is rotatably connected between the twoposts and the driving wheel 21 is connected to a crank to which twopedals are connected so that when the user rotates the crank, the flywheel 23 is rotated by the driving wheel 21 via the belt.

A magnetic resistance device 30 includes a support member 31 fixed on atransverse bar between the two posts of the frame 10 and a magnetassembly 32 is connected on the support member 31. The magnet assembly32 includes two magnets 321, 322 which are supported on the supportmember 31. The fly wheel 23 is rotatably located between the two magnets321, 322. The support member 31 is a U-shaped member including a baseplate and two sidewalls, wherein the base plate is fixed on thetransverse bar by a bolt and the two magnets 321, 322 are located on thebase plate and between the two sidewalls.

A circuit board 11 is electrically connected to the two magnets 321, 322and a control device 12 connected to the circuit board 11. The user mayoperate the control device 12 to adjust the current powering the magnets321, 322 so as to obtain different magnetic force.

Therefore, the magnet resistance device 30 can be independentlymanufactured regardless of shapes and sizes of the fly wheels 23. Themagnet resistance device 30 can be made modularized to reduce themanufacturing cost.

As shown in FIG. 5, the position of the magnet resistance device 30 canbe moved to any position on the frame 10 as long as the fly wheel 23goes between the two magnets 321, 322.

As shown in FIG. 6, the support member 31 is a U-shaped member includinga base plate and two sidewalls, wherein the two sidewalls are connectedto the shaft of the fly wheel 23 and the two magnets 321, 322 arelocated on the base plate. There can be two sets of the magneticresistance device 30 which are electrically connected in parallel witheach other to provide more powerful magnetic resistance to the fly wheel23. As shown in FIG. 7, the number of the magnet assembly 32 can bearranged in parallel or in series with each other so as to have desiredmagnetic forces.

FIG. 8 shows that the fly wheel 23 includes a generator set connected tospokes of the fly wheel 23, and coils 24 which are located along theperiphery of the fly wheel 23. The generator set and the coils can alsobe fixed on the pedals so as to control the voltages and currents, ormagnetic farce to be used.

The magnets 321, 322 can be manufactured modularized and the number ofthe magnets can be adjusted according to the specifications of the flywheel 23. The magnetic resistance device 30 is installed regardless ofthe thickness, the diameter or the shape of the fly wheels. Furthermore,the fly wheel 23 is not in contact with the magnets 321, 322 so that nonoise is produced. It is noted that the magnetic resistance device 40can be installed to either of the drive wheel 21 or the fly wheel 23 toachieve the same purpose.

While we have shown and described the embodiment in accordance with thepresent invention, it should be clear to those skilled in the art thatfurther embodiments may be made without departing from the scope of thepresent invention.

1. A magnetic resistance upright bike comprising: a frame and atransmission device connected to the frame, the transmission deviceincluding a driving wheel and a fly wheel which is driven by the drivingwheel; a magnetic resistance device including a support member fixed onthe frame and a magnet assembly connected on the support member, themagnet assembly including two magnets which are supported on the supportmember, one of the drive wheel and the fly wheel rotatably locatedbetween the two magnets, and a circuit board electrically connected tothe two magnets and a control device connected to the circuit board. 2.The bike as claimed in claim 1, wherein the support member is a U-shapedmember including a base plate and two sidewalls, the base plate is fixedon the frame and the two magnets are located on the base plate andbetween the two sidewalls.
 3. The bike as claimed in claim 1, whereinthe support member is a U-shaped member including a base plate and twosidewalls, the two sidewalls are connected to a shaft of the fly wheeland the two magnets are located on the base plate.
 4. The bike asclaimed in claim 1, wherein the fly wheel includes a generator setconnected to spokes of the fly wheel and coils which are connected on aperiphery of the fly wheel.